Species diversity patterns in Mediterranean grasslands

Journal of Vegetation Science - Tập 4 Số 2 - Trang 213-222 - 1993
J. Montalvo1, Miguel Á. Casado1, C. Levassor2, Francisco Díaz Pineda1
1Departamento Interunix'ersitarlo de Ecología, Facultad de Biología, Universidad Complutense, E-28040, Madrid, Spain
2Departamento Interunix'ersitarlo de Ecología, Facultad de Biología, Untxerstdad Autónoma, E‐28040, Madrid, Spain

Tóm tắt

Abstract. A field experiment involving herbivore exclusion, ploughing, and the combination of both was carried out over a period of 4 ‐ 5 yr in Mediterranean grasslands located along an elevational gradient. The empirical results provide a general hierarchical framework for understanding patterns of plant species diversity in thesegrasslands. In grazed grasslands, plant species density decreased as altitude increased, and this pattern was maintained through time. The reduced seasonality along the climatic gradient is suggested as the extrinsic, indirect control factor. Ploughing caused species loss, but after 4 yr the original diversity was recovered in most grasslands. Our hypothesis is that a negative feedback mechanism regulates species increase towards a characteristic level. A trend of species density reduction was observed in ungrazed grasslands. Plant‐herbivore interaction is considered to be essential for maintaining species diversity in grazed grasslands and for the recovery of diversity in mechanically disturbed grasslands.

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Tài liệu tham khảo

Allen T. F. H., 1982, Hierarchy. Perspectives for ecological complexity.

10.2307/2260265

10.2307/2260225

10.1086/284674

10.1007/978-1-4899-7325-2

Casado M. A., 1988, Diversity and pattern in plant communities, 159

10.1086/283257

Chesson P. L., 1986, Community ecology, 240

10.1086/283778

Chesson P. L., 1986, Community ecology, 229

10.2307/1939208

Collins S. L., 1988, Diversity and pattern in plant communities, 131

Connell J. H., 1975, Ecology and evolution of communities, 460

10.1007/BF00055209

10.1007/BF00047305

Glenn‐Lewin D. C., 1988, Diversity and pattern in plant communities, 115

Grime J. P., 1979, Plant strategies and vegetation processes.

Grime J. P., 1987, Colonization, succession and stability, 413

Grubb P. J., 1986, Community ecology, 207

Harper J. L., 1969, The role of predation in vegetational diversity, Brookhaven Symp. Biol., 22, 48

10.1146/annurev.es.05.110174.002223

Hassell M. P., 1976, The dynamics of competition andpreda‐tion.

10.1111/j.1365-2028.1984.tb00670.x

10.2307/1938902

10.1086/283366

10.1086/282171

10.1086/282687

10.2307/3565272

10.2307/3235709

Maranón T., 1985, Diversidad florística y heterogeneidad ambiental en una dehesa de Sierra Morena, Anal. Edaf. Agrobiol., 44, 1183

Maranón T., 1986, Plant species richness and canopy effect in the savanna‐like “dehesa” of S.W. Spain, Ecol. Medit., 12, 131

10.2307/1936547

10.1086/283181

McNaughton S. J., 1979, Serengeti: dynamics of an ecosystem, 46

10.2307/1942533

10.1086/283073

Meurk C. D., 1988, Diversity andpattern in plant communities, 47

10.1007/BF00049137

10.2307/3235714

10.1086/284839

10.1007/978-94-009-5798-5

10.2307/3236176

10.1007/BF00052445

10.2307/2403767

10.1007/BF00031699

Peco B., 1983, Diversité et structure spatiale des päturages méditerranéens en cours de succession, Ecol. Medit., 9, 223

10.1086/282697

Pielou E.C., 1975, Ecological diversity.

10.1007/BF00118404

10.2307/3235777

Schlichter T. M., 1978, Utilización de índices de diversidad en la evaluación de pastizales naturales en el centro‐oeste del Chubut, Ecología (Buenos Aires), 3, 125

Shannon C. E., 1949, The mathematical theory of communication.

Shmida A., 1988, Diversity and pattern in plant communities, 211

10.1146/annurev.es.16.110185.001413

10.1007/978-94-009-4055-0

Maarel E., 1988, Diversity and pattern in plant communities, 1

10.2307/3236103

10.2307/2257337

Wells T. C. E., 1971, The scientific management of animal and plant communities for conservation, 497

10.2307/1218190

10.2307/1934875

10.1007/BF00044994